CVE-2017-2475 in tvOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 10.3 is affected. Safari before 10.1 is affected. tvOS before 10.2 is affected. The issue involves the "WebKit" component. It allows remote attackers to conduct Universal XSS (UXSS) attacks via crafted use of frames on a web site.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/16/2024
The vulnerability identified as CVE-2017-2475 represents a critical cross-site scripting flaw within Apple's WebKit rendering engine that affected multiple Apple operating systems and browsers. This security weakness resides in the core web content processing component that powers Safari web browser and the underlying framework for iOS, macOS, and tvOS applications. The flaw specifically manifests in how WebKit handles frame elements when processing web content, creating a pathway for remote attackers to execute malicious code across different browser contexts.
The technical nature of this vulnerability stems from improper handling of frame-based content within the WebKit engine's security boundaries. When a malicious website crafts specific frame structures, it can exploit the way WebKit processes these elements to bypass traditional cross-site scripting protections. This allows attackers to inject malicious scripts that can execute in the context of other domains or applications, effectively enabling universal cross-site scripting attacks. The vulnerability operates by manipulating the frame hierarchy and security policies that normally prevent scripts from one origin from accessing resources in another, creating a scenario where attackers can escalate privileges and execute arbitrary code.
The operational impact of CVE-2017-2475 is significant given the widespread use of affected Apple products and browsers. Users of iOS versions prior to 10.3, Safari versions before 10.1, and tvOS versions before 10.2 faced elevated risk of exploitation through malicious websites that could leverage this flaw. The vulnerability could enable attackers to steal user sessions, access sensitive data, perform actions on behalf of users, and potentially gain deeper system access. This particular weakness aligns with CWE-79, which describes cross-site scripting vulnerabilities, and demonstrates how improper input validation and output encoding can create dangerous security gaps in web rendering engines.
Security researchers classified this vulnerability as particularly dangerous due to its potential for remote code execution and session hijacking. The exploitability of the flaw means that users could be compromised simply by visiting a malicious website, without requiring any specific user interaction beyond navigating to the compromised page. This makes it a prime target for phishing campaigns and drive-by download attacks. The vulnerability's classification under ATT&CK technique T1211, which covers exploitation for privilege escalation, highlights its potential to enable attackers to move laterally within affected systems and access additional resources beyond initial compromise.
The remediation approach for CVE-2017-2475 required users to upgrade to patched versions of Apple's operating systems and browsers, specifically iOS 10.3, Safari 10.1, and tvOS 10.2. Apple's patch addressed the underlying frame processing logic in WebKit to properly enforce security boundaries between different content contexts. Organizations needed to implement comprehensive patch management procedures to ensure all affected devices received updates promptly. Security professionals also recommended monitoring for suspicious web traffic and implementing additional network security controls to detect potential exploitation attempts. The vulnerability underscored the importance of maintaining up-to-date web browser components and highlighted how seemingly minor rendering engine flaws can create significant security risks for end users.